Contacts of the helix formed by residues 123 - 146 (chain A) in PDB entry 3NC0


Residue contacts within the protein are derived with the CSU software (Sobolev V., Sorokine A., Prilusky J., Abola E.E. and Edelman M. (1999) Automated analysis of interatomic contacts in proteins. Bioinformatics, 15, 327-332). A short description of the analytical approach is given at the end of the page.
For CSU analysis of other PDB entry

Note:
Non-standard 3 letter residue codes indicate a heterogroup. To identify and analyse, use LPC software

Legend:
Dist - nearest distance (Å) between atoms of two residues
Surf - contact surface area (Å2) between two residues
HB   - hydrophilic-hydrophilic contact (hydrogen bond)
Arom - aromatic-aromatic contact
Phob - hydrophobic-hydrophobic contact
DC   - hydrophobic-hydrophilic contact (destabilizing contact)
+/-  - indicates presence/absence of a specific contacts
*    - indicates residues forming contacts  by their side chain
       (including CA atoms)
Residues in contact with GLU 123 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     73A  MET*     3.4    20.3    -      -       +      -
    119A  CYS      3.7     0.4    -      -       -      -
    120A  VAL      3.0    26.0    -      -       -      +
    121A  GLU*     2.5    20.1    +      -       -      +
    122A  LYS*     1.3    81.0    -      -       -      +
    124A  LYS*     1.3    61.3    +      -       -      +
    125A  VAL*     2.6    37.2    +      -       +      +
    126A  TYR      2.8    12.6    +      -       -      -
    127A  ILE*     3.5     2.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 124 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    119A  CYS*     3.8    20.8    +      -       -      -
    120A  VAL*     3.9    28.6    +      -       +      +
    123A  GLU*     1.3    75.1    +      -       -      +
    125A  VAL*     1.3    52.2    +      -       +      +
    126A  TYR      3.4     0.4    -      -       -      -
    127A  ILE*     3.5    13.9    -      -       +      +
    128A  GLY*     2.5    34.9    +      -       -      -
    165A  GLN*     5.8     1.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 125 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     73A  MET*     3.2    24.0    -      -       +      -
     77A  TYR*     3.5    27.4    -      -       +      -
    123A  GLU*     2.6    24.5    +      -       +      +
    124A  LYS*     1.3    75.3    -      -       +      +
    126A  TYR*     1.3    56.5    +      -       -      +
    128A  GLY      3.8     0.3    -      -       -      -
    129A  LYS*     2.9    29.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 126 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     63A  VAL*     3.4    14.4    -      -       +      +
     73A  MET*     3.9    20.2    -      -       +      -
     76A  LYS*     3.8    41.6    -      -       +      +
     77A  TYR*     4.6     7.9    -      -       -      -
     80A  LEU*     3.3    33.4    -      -       +      -
    109A  LEU*     3.3    25.3    -      -       -      +
    112A  LYS*     5.8     0.3    +      -       -      -
    113A  THR*     3.8    19.7    -      -       +      -
    122A  LYS*     4.3    13.0    -      -       +      +
    123A  GLU      2.8    11.5    +      -       -      +
    125A  VAL*     1.3    73.9    -      -       -      +
    127A  ILE*     1.3    75.6    +      -       +      +
    129A  LYS*     3.8     3.4    -      -       -      +
    130A  LEU*     3.0    43.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 127 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    113A  THR*     3.8    33.4    -      -       -      +
    114A  SER*     4.1    12.8    -      -       -      +
    116A  ASP*     5.9     0.4    -      -       +      +
    119A  CYS*     3.9    22.9    -      -       +      +
    122A  LYS*     3.6    17.0    -      -       +      +
    123A  GLU      3.5    13.0    -      -       -      +
    124A  LYS*     3.5    12.8    -      -       -      +
    126A  TYR*     1.3    79.7    -      -       +      +
    128A  GLY*     1.3    58.5    +      -       -      +
    130A  LEU*     3.1    10.5    +      -       +      +
    131A  ASN*     2.9    47.5    +      -       -      +
    166A  ASN*     3.6    15.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 128 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    124A  LYS      2.5    22.3    +      -       -      -
    125A  VAL*     3.8     1.1    -      -       -      -
    127A  ILE*     1.3    73.6    -      -       -      +
    129A  LYS*     1.3    56.9    +      -       -      +
    131A  ASN*     3.5    11.3    +      -       -      +
    132A  MET*     2.9    28.4    +      -       -      +
    169A  VAL*     5.9     3.1    -      -       -      -
    173A  LEU*     4.3     5.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 129 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     77A  TYR*     3.3    41.7    +      -       +      +
     80A  LEU*     4.1    18.8    -      -       +      -
     81A  GLN*     4.7    12.8    -      -       -      +
     84A  GLU*     3.3    41.8    +      -       -      +
    125A  VAL      2.9    17.4    +      -       -      +
    126A  TYR      3.8     4.0    -      -       -      +
    128A  GLY*     1.3    72.3    -      -       -      +
    130A  LEU*     1.3    61.8    +      -       -      +
    132A  MET*     3.1    18.1    +      -       -      +
    133A  ILE*     2.9    42.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 130 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     80A  LEU*     3.9    28.2    -      -       +      +
     83A  LEU*     6.2     0.2    -      -       +      -
    106A  VAL*     4.5     9.1    -      -       +      +
    109A  LEU*     4.2    29.2    -      -       +      +
    110A  ILE*     4.2    18.1    -      -       +      +
    113A  THR*     3.3    26.0    -      -       -      +
    114A  SER*     5.9     0.7    -      -       -      +
    126A  TYR*     3.0    43.2    +      -       +      +
    127A  ILE*     3.3     9.4    -      -       -      +
    129A  LYS*     1.3    73.5    -      -       -      +
    131A  ASN*     1.3    66.5    +      -       -      +
    133A  ILE*     2.9    21.4    +      -       +      +
    134A  LEU*     3.0    11.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 131 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    110A  ILE*     3.9    15.7    -      -       -      +
    114A  SER*     4.9     0.4    -      -       -      -
    127A  ILE*     2.9    33.2    +      -       -      +
    128A  GLY*     3.6     9.4    -      -       -      +
    130A  LEU*     1.3    71.6    -      -       -      +
    132A  MET*     1.3    61.9    +      -       -      +
    134A  LEU*     3.1     6.9    +      -       -      +
    135A  VAL*     3.0    23.9    +      -       -      +
    166A  ASN*     2.9    44.3    -      -       -      +
    169A  VAL*     4.4     9.7    -      -       +      +
    170A  ILE*     3.5    21.5    -      -       +      +
    173A  LEU*     3.8    16.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with MET 132 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     84A  GLU*     4.3    14.8    -      -       -      +
    128A  GLY      2.9    15.5    +      -       -      +
    129A  LYS*     3.2    22.4    -      -       -      +
    130A  LEU      3.1     0.2    -      -       -      -
    131A  ASN*     1.3    77.1    -      -       -      +
    133A  ILE*     1.3    56.8    +      -       -      +
    135A  VAL*     3.3    28.3    +      -       +      -
    136A  GLN*     2.8    43.4    +      -       +      +
    139A  LYS*     6.4     0.2    -      -       +      -
    173A  LEU*     3.9    23.5    -      -       +      +
    177A  GLU*     3.7    27.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 133 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     80A  LEU*     3.5    54.5    -      -       +      +
     83A  LEU*     4.3     8.1    -      -       +      -
     84A  GLU*     4.3    12.3    -      -       +      -
     87A  ILE*     3.4    27.6    -      -       +      -
    106A  VAL*     4.2    19.1    -      -       +      -
    129A  LYS*     2.9    25.8    +      -       +      +
    130A  LEU*     2.9    12.1    +      -       +      +
    132A  MET*     1.3    75.2    -      -       -      +
    134A  LEU*     1.3    57.5    +      -       -      +
    136A  GLN*     3.0    11.5    -      -       +      +
    137A  ILE*     2.8    26.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 134 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    103A  LYS*     6.5     0.4    -      -       -      -
    106A  VAL*     4.1    10.7    -      -       +      +
    107A  VAL*     4.5    23.1    -      -       +      -
    110A  ILE*     3.5    31.9    -      -       +      -
    130A  LEU      3.0     5.7    +      -       -      -
    131A  ASN      3.3     8.7    -      -       -      +
    133A  ILE*     1.3    77.7    -      -       -      +
    135A  VAL*     1.3    51.8    +      -       -      +
    137A  ILE*     2.9    14.7    +      -       +      +
    138A  LEU*     2.8    58.4    +      -       +      +
    146A  TRP*     5.0     4.9    -      -       -      +
    149A  PHE*     4.7    10.8    -      -       +      -
    153A  ILE*     6.3     0.4    -      -       +      -
    170A  ILE*     4.0    28.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 135 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    131A  ASN      3.0    15.6    +      -       -      +
    132A  MET*     3.5    24.9    -      -       +      +
    134A  LEU*     1.3    75.3    -      -       -      +
    136A  GLN*     1.3    63.8    +      -       -      +
    138A  LEU*     3.7     9.2    -      -       +      +
    139A  LYS*     2.9    25.4    +      -       +      +
    170A  ILE*     3.7    30.7    -      -       +      +
    173A  LEU*     3.7    16.4    -      -       +      -
    174A  LEU*     3.8    26.0    -      -       +      +
    177A  GLU*     3.8    20.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLN 136 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     84A  GLU*     3.1    30.0    +      -       +      +
     87A  ILE*     3.9    13.8    -      -       +      +
     88A  LYS*     3.1    46.6    -      -       +      +
    132A  MET*     2.8    36.6    +      -       +      +
    133A  ILE*     3.0    21.1    +      -       +      +
    135A  VAL*     1.3    77.1    -      -       -      +
    137A  ILE*     1.3    59.1    +      -       -      +
    139A  LYS*     3.3    34.5    +      -       -      +
    140A  GLN*     3.8    10.9    +      -       -      +
    177A  GLU*     5.9     1.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 137 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     87A  ILE*     3.5    31.9    -      -       +      -
     91A  TRP*     3.8    16.4    -      -       +      -
    102A  ILE*     3.5    32.3    -      -       +      -
    103A  LYS*     4.5    14.8    -      -       +      -
    106A  VAL*     4.2    15.9    -      -       +      -
    133A  ILE      2.8     9.6    +      -       -      +
    134A  LEU*     2.9    17.0    +      -       +      +
    136A  GLN*     1.3    73.0    -      -       -      +
    138A  LEU*     1.3    57.6    +      -       -      +
    139A  LYS      3.1     1.3    -      -       -      -
    140A  GLN*     2.7    29.2    +      -       -      +
    141A  GLU*     3.4    24.0    +      -       +      +
    146A  TRP*     4.9     5.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 138 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    134A  LEU*     2.8    35.1    +      -       +      +
    135A  VAL*     3.7    18.4    -      -       +      +
    137A  ILE*     1.3    72.8    -      -       -      +
    139A  LYS*     1.3    62.4    +      -       -      +
    140A  GLN      2.8     0.2    +      -       -      -
    141A  GLU*     3.0     0.4    +      -       -      -
    142A  TRP*     2.7    45.0    +      -       +      +
    143A  PRO*     4.5     1.4    -      -       -      +
    146A  TRP*     4.1    17.0    -      -       +      -
    149A  PHE*     3.4    60.3    -      -       +      -
    170A  ILE*     4.7     3.1    -      -       +      -
    174A  LEU*     4.1    23.8    -      -       +      -
    194A  LEU*     4.8     2.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 139 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     88A  LYS*     5.9     4.2    -      -       -      +
    132A  MET*     6.4     0.2    -      -       +      -
    135A  VAL*     2.9    14.1    +      -       +      +
    136A  GLN*     3.3    32.1    +      -       -      +
    138A  LEU*     1.3    75.9    -      -       -      +
    140A  GLN*     1.3    54.8    +      -       +      +
    143A  PRO*     6.0     0.2    -      -       -      +
    174A  LEU*     5.1     3.7    -      -       +      +
    177A  GLU*     3.1    44.7    +      -       +      +
    178A  VAL*     5.5     4.9    -      -       +      -
    185A  GLN*     3.8    19.2    +      -       -      +
    186A  ILE*     3.7    36.5    -      -       +      +
    190A  LYS*     2.7    36.5    +      -       -      +
    194A  LEU*     4.2    17.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 140 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     87A  ILE*     3.7    25.1    -      -       +      +
     88A  LYS*     4.6     7.4    -      -       +      +
     91A  TRP*     3.9    28.1    +      -       +      +
     92A  LYS*     4.0    32.3    -      -       -      +
    136A  GLN      3.9    10.5    -      -       -      +
    137A  ILE*     2.7    19.5    +      -       -      +
    139A  LYS*     1.3    73.9    -      -       +      +
    141A  GLU*     1.3    59.8    +      -       -      +
    144A  LYS*     5.6     0.9    -      -       -      +
    145A  HIS*     5.3     0.9    -      -       -      -
    190A  LYS*     4.0    18.7    +      -       -      +
   1024A  GLU*     4.3    19.8    -      -       -      +
   1032A  ASP*     4.9     8.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 141 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     91A  TRP*     3.6    27.0    +      -       -      +
     96A  ARG*     4.2     7.1    +      -       -      -
     99A  CYS*     4.8     3.5    -      -       -      +
    103A  LYS*     3.0    42.2    +      -       -      +
    137A  ILE*     3.8    13.4    -      -       +      +
    138A  LEU      3.0     1.0    +      -       -      -
    139A  LYS      3.6     0.4    -      -       -      -
    140A  GLN*     1.3    82.3    -      -       -      +
    142A  TRP*     1.3    73.9    +      -       -      +
    143A  PRO*     2.8    10.5    -      -       -      +
    144A  LYS*     3.1     8.7    +      -       -      -
    145A  HIS*     3.1    51.1    +      -       +      +
    146A  TRP*     3.7     8.6    +      -       +      -
----------------------------------------------------------
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Residues in contact with TRP 142 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    138A  LEU*     2.7    40.2    +      -       +      +
    141A  GLU*     1.3    71.2    -      -       -      +
    143A  PRO*     1.3    68.4    -      -       +      +
    146A  TRP*     2.9    38.8    +      -       -      +
    147A  PRO*     4.3     2.0    +      -       -      +
    149A  PHE*     3.5    41.7    -      +       +      +
    150A  ILE*     4.3    23.4    -      -       +      +
    174A  LEU*     5.0    10.1    -      -       +      -
    178A  VAL*     5.8     0.4    -      -       +      -
    194A  LEU*     3.6    24.7    -      -       +      -
    197A  SER*     3.1    52.7    -      -       -      -
    198A  MET*     3.3    30.7    -      -       +      -
    201A  GLU*     4.4    13.4    +      -       +      -
----------------------------------------------------------
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Residues in contact with PRO 143 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    138A  LEU      4.5     0.4    -      -       -      +
    139A  LYS      6.0     0.2    -      -       -      +
    141A  GLU*     3.2     4.7    -      -       -      +
    142A  TRP*     1.3   112.9    -      -       +      +
    144A  LYS*     1.3    78.8    +      -       +      +
    145A  HIS      3.5     0.2    +      -       -      -
    147A  PRO*     3.6    18.1    -      -       +      +
    193A  HIS*     3.3    36.3    -      -       +      +
    194A  LEU*     4.4     7.9    -      -       +      -
    197A  SER*     3.9    16.4    -      -       -      +
    201A  GLU*     6.0     1.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 144 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    140A  GLN      5.6     0.4    -      -       -      +
    141A  GLU*     3.1     9.7    +      -       -      +
    143A  PRO*     1.3    85.5    -      -       +      +
    145A  HIS*     1.3    81.6    +      -       +      +
    146A  TRP      3.9     0.2    +      -       -      -
    147A  PRO*     4.1     8.7    -      -       -      +
    190A  LYS*     6.4     1.8    -      -       -      +
    193A  HIS*     3.2    37.6    +      -       +      +
   1032A  ASP*     3.5    38.8    +      -       -      +
   1034A  PHE*     4.4    13.8    -      -       -      -
----------------------------------------------------------
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Residues in contact with HIS 145 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     96A  ARG*     3.0    44.7    +      -       -      +
    103A  LYS*     3.3    17.5    +      -       -      -
    140A  GLN      5.3     0.7    -      -       -      -
    141A  GLU*     3.1    33.8    +      -       +      +
    144A  LYS*     1.3    93.5    +      -       +      +
    146A  TRP*     1.3    58.7    +      -       -      +
    147A  PRO*     3.3     9.3    -      -       -      +
   1030A  THR*     5.9     1.2    -      -       -      +
   1032A  ASP*     4.3    17.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with TRP 146 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    103A  LYS*     3.3    34.6    -      -       +      +
    107A  VAL*     4.6    23.8    -      -       +      +
    134A  LEU*     5.0     4.9    -      -       -      +
    137A  ILE*     4.9     5.5    -      -       +      +
    138A  LEU*     4.1    16.8    -      -       +      +
    141A  GLU*     3.7    10.5    +      -       +      +
    142A  TRP*     2.9    31.9    +      -       -      +
    145A  HIS*     1.3    79.1    -      -       -      +
    147A  PRO*     1.3    68.1    -      -       +      +
    148A  THR*     3.4    17.0    -      -       -      -
    149A  PHE*     3.1    60.2    +      +       +      +
    152A  ASP*     3.5    14.4    -      -       +      -
    153A  ILE*     6.2     0.7    -      -       +      -
----------------------------------------------------------
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A short description of the analytical approach
The contact analysis used in this page is based upon the approach developed in: Sobolev V., Wade R.C., Vriend G. and Edelman M. PROTEINS (1996) 25, 120-129. Contact legitimacy depends on the hydrophobic-hydrophilic properties of the contacting atoms. In order to define it, for each inter-atomic contact, eight atom classes have been introduced:


   I  Hydrophilic      - N and O that can donate and accept hydrogen bonds
                         (e.g., oxygen of hydroxyl group of Ser. or Thr)
  II  Acceptor         - N or O that can only accept a hydrogen bond
 III  Donor            - N that can only donate a hydrogen bond
  IV  Hydrophobic      - Cl, Br, I and all C atoms that are not in
                         aromatic rings and do not have a covalent bond to
                         a N or O atom
   V  Aromatic         - C in aromatic rings irrespective of any other 
                         bonds formed by the atom
  VI  Neutral          - C atoms that have a covalent bond to at least one
                         atom of class I or two or more atoms from class II
                         or III; atoms; S, F, P, and metal atoms in all cases
 VII  Neutral-donor    - C atoms that have a covalent bond with only one
                         atom of class III
VIII  Neutral-acceptor - C atoms that have a covalent bond with only 
                         one atom of class II
For each pair of contacts the state of legitimacy is shown below:

Legend:
+, legitimate
-, illegitimate
------------------------------------------------------------
  Atomic class           I  II  III   IV   V   VI  VII  VIII
------------------------------------------------------------
   I  (Hydrophilic)      +   +    +    -   +   +    +    +
  II  (Acceptor)         +   -    +    -   +   +    +    -
 III  (Donor)            +   +    -    -   +   +    -    +
  IV  (Hydrophobic)      -   -    -    +   +   +    +    +
   V  (Aromatic)         +   +    +    +   +   +    +    +
  VI  (Neutral)          +   +    +    +   +   +    +    +
 VII  (Neutral-donor)    +   +    -    +   +   +    -    +
VIII  (Neutral-acceptor) +   -    +    +   +   +    +    -
------------------------------------------------------------
Warning!
Atom classes for heterogroups are automatically assigned based on the atomic coordinates. However, in three cases (see below) the automatic assignment is currently ambiguous. In these cases, the user is advised to manually analyse the full list of contacts using LPC software.
1. Carbon atoms belonging to a 4-, 5- or 6-member ring are 
   considered "aromatic" (Class V) if the ring is approximately
   planar, and "hydrophobic" (Class IV) or "neutral" (Classes
   VI, VII, VIII) if the ring is non-planar.
2. The oxygen atom of a carbonyl or hydroxy group is considered
   "hydroxy" (Class I) if the CO bond is longer than 1.29 Å, and
   "carbonyl" (Class II) if shorter.
3. All nitrogen atoms are considered "hydrophilic" (Class I).

Please E-mail any questions and/or suggestions concerning this page to Vladimir.Sobolev@weizmann.ac.il